Eclipse RCP Step by Step

Singleton Design Pattern Singleton Design Pattern means able to create only one object of the class. When you want to restrict some class from being created multiple objects, this design pattern is being used. First step of creating the class singleton is to make it's constructor private so other class can't call it anytime and create and object of it. Then create a static method "getInstance" which will return the object of the same class . Here its SingletonExampleClass . This method (getInstance) is created static , because this class has private constructor so we won't have it's object with us to access this class first time. Synchronized block is used stop multiple threads to access the instantiation code block at the same time, else it will be able to create multiple objects. now assume that two thread are there T1 and T2. Not Thread T1 access this method first and acquire the lock. While Thread T1 was accessing the code inside Synchronized bl

How to resolve : print() on closed filehandle in perl Error "print() on closed filehandle" generated in the following condition ( it is on of possible cause of it) -------------------------- BEGIN Code --------------------------------------- my $inputFile = '/this/is/path/of/your/input/file.txt'; open(MYINPUTFILE, ">","$inputFile"); print MYINPUTFILE "any data"; close(MYINPUTFILE); -------------------------- END Code --------------------------------------- here if you don't have permission to access the path '/this/is/path/of/your/input/file.txt' or the path (of parent directory) does not exist then it will throuw the error : print() on closed filehandle To resolve this better to make practice as follow while opening the file: -------------------------- BEGIN Code --------------------------------------- open(MYINPUTFILE, ">","$inputFile") or die "ERROR ::: unable access the file&